Grinding device

Abstract

The processing load applied to the workpiece in the polishing device is precisely controlled. [Solution] The polishing device 1 includes a head unit 5 positioned above the workpiece 2 so as to be able to move up and down, an upper platen 8 for polishing the upper surface of the workpiece 2, and a plurality of suspensions 9 that transmit the rotation of the upper platen spindle provided on the head unit 5 to the upper platen 8. Furthermore, it includes a sensor for detecting the amount of vertical displacement of each suspension 9, an adjustment member that connects the suspensions 9 and the upper platen 8 and adjusts the distance between the tip of each suspension 9 and the upper platen 8, and a display unit that displays the amount of vertical displacement of each suspension 9 based on the detection signal from the sensor.

Description

Technical Field

[0006] , ,

[0005] ,

[0007] ,

[0001] The present invention relates to a polishing apparatus such as a double-sided polishing apparatus.

Background Art

[0002] In a double-sided polishing apparatus, a workpiece is sandwiched between platens each having a processing reference surface called an upper platen and a lower platen, and polishing is performed by rotating the lower platen, the upper platen, or both. During the polishing process, an abrasive called slurry is contained or impregnated. Alternatively, a sheet-like abrasive tool called a polishing pad is used.

[0003] As a double-sided polishing apparatus as described above, for example, Patent Document 1 discloses a polishing apparatus including a holder for a workpiece called a carrier, and provided with a polishing pad such as a polishing cloth, a polishing sheet, or a buff as an abrasive tool.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] )]]In a double-sided polishing apparatus, factors such as the way of applying load to the workpiece, the shape of the platen, the physical properties of the polishing pad, and the physical properties of the slurry affect the processing time and the finish accuracy of the processed surface. In particular, the load applied to the workpiece is a major factor for the processing time.

[0006] In the double-sided polishing apparatus of Patent Document 1, a polishing pad or slurry is used to perform polishing, and a load is applied to the platen to perform polishing. At that time, the load applied to the workpiece is set using a load measuring device called a load cell that converts the load into an electrical signal.

[0007] However, the load setting method for the double-sided polishing apparatus described in Patent Document 1 only controls the load by the total amount of load applied to the workpiece by the entire polishing platen. Therefore, it was not possible to finely control the processing time, the finish accuracy of the processed surface, or the shape of the polishing platen.

[0008] The object of the present invention is to provide a polishing apparatus that can precisely control the processing load applied to a workpiece.

[0009] Another object of the present invention is to provide a polishing apparatus capable of controlling the shape of the surface plate. [Means for solving the problem]

[0010] The polishing apparatus of the present invention is a polishing apparatus for polishing a workpiece, comprising: a head portion incorporating an upper platen spindle and positioned to move vertically above the workpiece; an upper platen for polishing the upper surface of the workpiece; a drive body provided at the lower end of the upper platen spindle; a plurality of suspension beam members, the base end of which is fixed to the drive body and the tip end of which is connected to the upper platen to transmit the rotation of the upper platen spindle to the upper platen; a sensor for detecting the vertical displacement of each of the suspension beam members; an adjustment member for connecting the suspension beam members and the upper platen and adjusting the distance between the tip end of the suspension beam members and the upper platen; and a display unit for displaying the vertical displacement of each of the suspension beam members based on the detection signal from the sensor. [Effects of the Invention]

[0011] According to the present invention, the processing load applied to the workpiece in the polishing apparatus can be precisely controlled. Furthermore, the shape of the polishing platen can be controlled in the polishing apparatus. [Brief explanation of the drawing]

[0012] [Figure 1] This is a perspective view showing the structure of a polishing apparatus according to an embodiment of the present invention. [Figure 2] Figure 1 is a schematic diagram illustrating a non-contact method for measuring the displacement of a suspension beam member in a polishing apparatus. [Figure 3] This is a schematic diagram showing a contact-type measurement method for the displacement of the suspension beam member in the polishing apparatus shown in Figure 1. [Figure 4] This is a schematic diagram showing a measurement method for a first modified example of the displacement amount of the suspension beam member in the polishing apparatus shown in Figure 1. [Figure 5] Figure 1 is a block diagram of the control system for the polishing apparatus. [Figure 6] Figure 1 shows the structure of the adjustment member provided in the polishing apparatus, where (a) is a front view and (b) is a side view. [Figure 7] Figure 6 is a cross-sectional view showing the detailed structure of the adjustment member. [Figure 8] Figure 1 is an output diagram showing an example of the detection results of the displacement amount of each suspension beam member in the polishing apparatus (uniform upper platen state). [Figure 9] Figure 1 is an output diagram showing an example of the detection results of the displacement amount of each suspension beam member in the polishing apparatus (upper platen non-uniform state). [Figure 10] This is an output diagram showing an enlarged view of the detection results in sections A and B shown in Figure 9. [Figure 11] Figure 1 is an output diagram showing an example of the detection results of the displacement amount of each suspension beam member in the polishing apparatus (with uniform workpiece height). [Figure 12] Figure 1 is an output diagram showing an example of the detection results of the displacement amount of each suspension beam member in the polishing apparatus (in a state of uneven workpiece height). [Figure 13] This is a cross-sectional view showing the structure of a second modified example of the adjustment member provided in the polishing device shown in Figure 1. [Modes for carrying out the invention]

[0013] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0014] In this embodiment, as an example of the polishing apparatus 1, a suspension type double-sided polishing apparatus will be taken up and described. As shown in FIG. 1, the polishing apparatus 1 of this embodiment has a lower platen 13 that rotates in a horizontal plane, and an upper platen 8 that is disposed opposite to the lower platen 13 and rotates. A polishing pad 13a as a lower polishing tool is annularly attached to the upper surface of the lower platen 13. On the other hand, on the lower surface of the upper platen 8, a polishing pad 8a shown in FIG. 2 that is annular corresponding to the polishing pad 13a is attached as an upper polishing tool. The upper platen 8 is movable in the vertical direction Z and is movable closer to and away from the lower platen 13. That is, the polishing apparatus 1 is an apparatus for polishing both the upper and lower surfaces of a workpiece (workpiece to be processed) 2, and performs lapping and polishing of a disk substrate as the workpiece 2 by the polishing pads 13a and 8a as polishing tools.

[0015] The main configuration of the polishing apparatus 1 will be described. As shown in FIGS. 1 and 2, the polishing apparatus 1 includes a head portion 5 in which an upper platen spindle 5a is incorporated and is disposed above the workpiece 2 so as to be vertically movable, an upper platen 8 that polishes the upper surface of the workpiece 2, and a lower platen 13 that polishes the lower surface of the workpiece 2. Further, the polishing apparatus 1 includes a column portion 3 that supports a motor 6 for rotating the upper platen 8, and an operation panel 4 that sets the processing load applied to the workpiece 2 and the like. Furthermore, as shown in FIG. 2, the polishing apparatus 1 includes a suspension base (drive body) 10 provided at the lower end portion of the upper platen spindle 5a, a plurality of suspensions (suspension beam members) 9 whose base end portions 9a are fixed to the suspension base 10 and whose tip end portions 9b are connected to the upper platen 8 to transmit the rotation of the upper platen spindle 5a to the upper platen 8, and sensors 11 that detect the displacement amount of each of the suspensions 9 in the vertical direction Z. Each of the plurality of suspensions 9 and the upper platen 8 are connected by an adjustment member 12, and the adjustment member 12 can adjust the distance L1 (see FIG. 8) between the tip end portion 9b of the suspension 9 and the upper platen 8.

[0016] Since the grinding device 1 is a suspension type, the upper platen 8 is suspended. Specifically, the upper platen 8 is lifted by a plurality of suspensions 9 and adjustment members 12 via an air cylinder 7 provided at the upper end of the head portion 5. The air cylinder 7 lifts the upper platen 8 via a load cell (not shown), and the load cell detects the weight of the upper platen 8 including the plurality of suspensions 9 and adjustment members 12. That is, the lifting load of the upper platen 8 including the plurality of suspensions 9 and adjustment members 12 is detected by the load cell, and the grinding load applied to the workpiece 2 is set based on this detection result. That is, the suspension type double-sided grinding device (grinding device 1) has a structure in which the weight of the upper platen 8 is applied to the workpiece 2 as the grinding load.

[0017] Next, the structure and operation of the lower platen 13 side of the grinding device 1 shown in FIG. 1 will be described. A sun gear 15 having an outer diameter slightly smaller than the inner diameter of the grinding pad 13a is rotatably provided at the rotation center portion of the lower platen 13. An annular internal gear 16 having an outer diameter slightly larger than this outer diameter is provided so as to surround the lower platen 13 outside the grinding pad 13a. That is, the internal gear 16 is disposed outside the sun gear 15 in the radial direction D2 and is rotationally driven.

[0018] And, a plurality of carriers 14 are arranged on the upper surface of the grinding pad 13a provided on the lower platen 13, and the external gear portions formed on the outer peripheral portions of the respective carriers 14 are engaged with the sun gear 15 and the internal gear 16. A plurality of circular holding holes 14a for holding the workpiece 2 are formed in each carrier 14, and the thickness of the carrier 14 is formed thinner than the thickness of the workpiece 2. The number of carriers 14 arranged on the lower platen 13 and the number of holding holes 14a formed in one carrier 14 are not limited to the numbers shown in the figure and can be any number.

[0019] When each carrier 14 is engaged with the sun gear 15 and the internal gear 16 and rotated along with them, each carrier 14 rotates on its own axis while revolving around the sun gear 15. Furthermore, the workpiece 2 moves horizontally in a cycloidal or trochoidal curve, in contact with the upper and lower polishing pads 8a and 13a in the horizontal plane, as moved by the carrier 14. In this way, each workpiece 2 moves from the inner circumference to the outer circumference of the upper and lower polishing pads 8a and 13a as well as in the circumferential direction along the polishing pads 8a and 13a, so that all workpieces 2 can be averaged out and processed with a precision higher than the precision of the device.

[0020] The polishing apparatus 1 of this embodiment is of the suspension type, in which the upper platen 8 is suspended and supported by a plurality of suspensions 9. The upper platen 8 is, for example, disc-shaped, and each suspension 9 extends in the radial direction D1 of the upper platen 8 and is arranged at regular intervals in the outer peripheral direction R of the upper platen 8. In the polishing apparatus 1 shown in Figure 1, for example, 10 suspensions 9 are arranged on the upper platen 8 at regular intervals in the outer peripheral direction R of the upper platen 8, and the upper platen 8 is supported by these 10 suspensions 9. In other words, the 10 suspensions 9 are arranged on the upper platen 8 at 36° intervals. However, the number of suspensions 9 supporting the upper platen 8 is not limited to 10, and there may be more than 10.

[0021] Furthermore, each suspension 9 is equipped with a sensor 11 that detects the amount of displacement (deflection) of the tip 9b of each suspension 9 in the vertical Z direction, as shown in Figure 2. The sensor 11 shown in Figure 2 employs an optical displacement meter 11a as a non-contact sensor. Specifically, the optical displacement meter 11a is attached to a bracket 11b provided on the suspension base 10, and the light 11c emitted from the optical displacement meter 11a is reflected by a mirror 11d and irradiated onto the tip 9b of the suspension 9, thereby detecting the amount of displacement of the tip 9b of the suspension 9 in the vertical Z direction. Since such an optical displacement meter 11a is provided for each of the 10 suspensions 9, it becomes possible to detect the amount of displacement of the tip 9b of each suspension 9 in the vertical Z direction.

[0022] The sensor 11 may also be a contact-type sensor. The sensor 11 shown in Figure 3 employs a digital gauge 11e as a contact-type sensor. Specifically, the digital gauge 11e is attached to a bracket 11f provided on the suspension base 10, and by bringing this digital gauge 11e into contact with the tip 9b of the suspension 9, the amount of vertical displacement Z of the tip 9b of the suspension 9 is detected. By providing such a digital gauge 11e for each of the 10 suspensions 9, the amount of vertical displacement Z of the tip 9b of each suspension 9 can be detected.

[0023] Furthermore, as shown in the first modified example in Figure 4, a strain gauge 11g for detecting the amount of strain on the suspension 9 may be used as the sensor 11. Specifically, by providing the strain gauge 11g at any point on the suspension 9, the amount of displacement of the suspension 9 can be detected based on the amount of strain detected by the strain gauge 11g.

[0024] As shown in Figure 5, the polishing apparatus 1 of this embodiment has a display unit 17 that displays the amount of displacement (deflection) of each suspension 9 in the vertical Z direction based on detection signals from a plurality of sensors 11. That is, the detection signals of the displacement of the suspension 9 from the plurality of sensors 11 are transmitted to the control unit 3a, and the control unit 3a further transmits the displacement signals of each suspension 9 to the display unit 17, and this displacement is displayed, for example, as an image. Alternatively, a printer or the like may be used instead of the display unit 17, and the displacement of each suspension 9 in the vertical Z direction may be output from the printer.

[0025] Furthermore, as shown in Figures 6(a) and (b), the polishing apparatus 1 has an adjustment member 12 that connects the suspension 9 to the upper platen 8 and allows adjustment of the distance L1 (see Figure 8) between the tip 9b of the suspension 9 and the upper platen 8. In other words, the tip 9b of each of the 10 suspensions 9 and the upper platen 8 are connected by the adjustment member 12. That is, the upper platen 8 is provided with 10 suspensions 9 and 10 adjustment members 12 that connect the tip 9b of each suspension 9 to the upper platen 8.

[0026] Each adjustment member 12 includes a holder 12b on which a roller 12a is provided, positioned on the upper surface of the tip 9b of the suspension 9; a beam-side threaded member 12d screwed to the holder 12b; a base plate-side threaded member 12e which is oriented in the opposite direction to the beam-side threaded member 12d and screwed to the upper base plate 8; and a turnbuckle (rotating body) 12f screwed to the beam-side threaded member 12d and the base plate-side threaded member 12e. Fixing nuts 12c are positioned on both the upper and lower sides of the turnbuckle 12f, and when adjusting the distance L1 (see Figure 8) between the suspension 9 and the upper base plate 8 by rotating the turnbuckle 12f, the fixing nuts 12c are loosened to make the adjustment.

[0027] As shown in Figure 7, the threads on the beam-side threaded member 12d and the surface plate-side threaded member 12e are opposite in direction. For example, if the beam-side threaded member 12d is a right-hand thread, the surface plate-side threaded member 12e is a left-hand thread, and when the turnbuckle 12f is rotated, the beam-side threaded member 12d and the surface plate-side threaded member 12e move closer together or further apart. This makes it easy to adjust the distance L1 between the tip 9b of the suspension 9 and the upper surface plate 8 by rotating the turnbuckle 12f.

[0028] In the polishing apparatus 1, by having the above-described configuration, the displacement amount of each of the multiple suspensions 9 that suspend the upper platen 8 is detected, and the distance L1 between the suspension 9 and the upper platen 8 is changed based on this detection result, thereby making it possible to control the amount of load applied to the workpiece 2 at the position of each suspension 9 on the disc-shaped upper platen 8 and the degree of deformation of the upper surface of the upper platen 8. In other words, in the multiple suspensions 9 that support the upper platen 8, it becomes possible to control the amount of weight that each suspension 9 is responsible for for each suspension 9.

[0029] To explain in more detail, each of the multiple suspensions 9 supporting the upper platen 8 is also a beam, and each of these beams deflects under the weight of the upper platen 8. Furthermore, the upper platen 8 forms a wave-like deflection along the outer circumference R of the upper platen 8, starting from the part supported by the beams (suspensions 9). Since the suspended double-sided polishing device (polishing device 1) has a structure that applies the weight of the upper platen 8 as a processing load to the workpiece 2, the amount of deflection of the beams decreases by the amount of the applied load. In other words, the load borne by the beams (suspensions 9) decreases by the amount of the applied load. Therefore, in the polishing device 1 of this embodiment, by measuring the rate of change of the load applied to these beams as the amount of deflection (displacement) of the beams, it is possible to evaluate the rate of load around the part supported by the beams (suspensions 9).

[0030] For example, in a polishing apparatus 1, if an optical displacement meter 11a is provided as a non-contact sensor capable of measuring the displacement of the tip 9b of the suspension 9 as shown in Figure 2, the initial state is defined as the upper platen 8 not touching the workpiece 2. Furthermore, by adjusting the deflection (displacement) of each suspension 9 based on this initial state and with the state in which the entire weight of the upper platen 8 is supported by the workpiece 2 as the upper limit, the deflection value of each suspension 9 can be converted into a ratio of the load placed on the area around the part supported by the suspension 9. Specifically, the difference between the measured deflection (displacement) of each suspension 9 when the upper platen 8 is not in contact with the workpiece 2 and the measured deflection (displacement) of each suspension 9 when the entire load is placed on the workpiece 2 is calculated. Then, the deflection (displacement) of each suspension 9 is adjusted based on this difference value, and the proportion of the load borne by each suspension 9 is calculated from the measured deflection (displacement) of each suspension 9 shown by the optical displacement meter 11a and displayed on the display unit 17 shown in Figure 5. This makes it possible to evaluate the displacement of each suspension 9, which is a beam, as an additional load around the part supported by the suspension 9. This makes it possible to evaluate whether the load set on the workpiece 2 is being applied by the upper platen 8. In other words, the amount of deflection of the tip 9b of each suspension 9 makes it possible to know the additional load around the part supported by each suspension 9, and thereby evaluate whether the intended load is being applied to the workpiece 2 from the upper platen 8. To put it another way, it is possible to know the state of the load borne by each suspension 9, and by controlling the load borne by each suspension 9, it is possible to contribute to more precise polishing.

[0031] Also, depending on the material and physical properties of the upper platen 8, by arbitrarily changing the amount of deflection of the suspension 9 from the relationship between the suspension 9, the adjustment member 12, and the upper platen 8, the waveform shape in the outer peripheral direction R of the upper platen 8 shown in FIG. 1 can be arbitrarily changed. For example, FIG. 8 shows an example of the image 17a output to the display unit 17. In the image 17a, the A part, B part, C part, and D part, which are the tip positions of any suspension 9 in the outer peripheral direction R of the upper platen 8, are taken up, and it is shown that the distances L1 between the upper platen 8 and the suspension 9 (here, the center of the roller 12a) in these A part, B part, C part, and D part are equal. That is, since the distances L1 between the upper platen 8 and the suspension 9 in the A part, B part, C part, and D part in the outer peripheral direction R of the upper platen 8 are equal, the shape in the thickness direction of the upper platen 8 is a uniform shape in the outer peripheral direction R.

[0032] On the other hand, in the image 17b shown in FIG. 9, the adjustment member 12 at the position of the B part is adjusted so that the distance L2 between the upper platen 8 and the suspension 9 at the position of the B part becomes L1 < L2 as shown in FIG. 10. In this state, the upper and lower surfaces of the upper platen 8 at the position of the B part are in a lowered state compared to the A part, C part, and D part, and the shape in the thickness direction of the upper platen 8 is a non-uniform shape in the outer peripheral direction R. In other words, by arbitrarily changing the amount of deflection of the suspension 9 at an arbitrary location, the load borne by the suspension 9 is changed, and this changes the shape of the connection part of the upper platen 8. As a result, it becomes possible to arbitrarily change the shape in the outer peripheral direction R of the upper platen 8, and it becomes possible to control the direction of the fine processing load on the workpiece 2. This is an important factor that affects the polishing time or polishing quality. For example, in the state shown in FIG. 10, since the distance L2 between the upper platen 8 and the suspension 9 at the position of the B part is adjusted so that L1 < L2, the amount of deflection of the suspension 9 at the B part is smaller than that of the suspension 9 at the A part. As a result, since the load borne by the suspension 9 at the B part is smaller than that of the suspension � at the A part, the relationship between the processing loads (polishing loads) F1 and F2 applied from the upper platen 8 to the workpiece 2 is F1 < F2.

[0033] As described above, by changing the amount of deflection of the suspension 9 at any position, the shape of the wave pattern in the outer circumference R of the upper platen 8 can be changed arbitrarily. For example, by changing the amount of deflection of the suspension 9 at any position, it is possible to change the size of the distance (range) between the top of the upper surface and the bottom of the lower surface in the wave pattern in the outer circumference R of the upper platen 8 (the vertical size of the wave pattern). This means that, for example, when increasing the polishing speed, the distance (range) between the top of the upper surface and the bottom of the lower surface of the upper platen 8 can be set to be larger, or when increasing the polishing accuracy, the distance (range) between the top of the upper surface and the bottom of the lower surface of the upper platen 8 can be set to be smaller, and these settings can be selected by the customer during the polishing process.

[0034] Furthermore, if the polishing device 1 detects a value that is clearly different from the measured deflection amount of each of the multiple suspensions 9 in relation to the processing load set, it means that the thickness of the workpiece 2 has changed, and this can be detected as an abnormal condition. For example, when processing multiple workpieces 2 simultaneously on the lower platen 13, the deflection amount of the multiple suspensions 9 at arbitrary positions can be measured in advance during the pre-polishing process, and the magnitude of the deflection amount of each suspension 9 can be compared with a preset reference value for the deflection amount to detect an abnormality in the thickness of the workpiece 2 at any given position. In other words, if there is an abnormality in the thickness of any workpiece 2 due to the adhesion of foreign matter, the polishing device 1 can extract a value that is different from the reference converted load, and thus it becomes possible to detect that abnormality in thickness as a fluctuation in the deflection amount of the suspension 9.

[0035] To explain in more detail, image 17c in Figure 11 shows the case where the thickness of workpiece 2 in sections A, B, C, and D is all within tolerance, meaning that each has the same thickness. Therefore, the amount of deflection of each suspension 9 in sections A, B, C, and D is also the same, and the distance L1 between the upper platen 8 and the suspension 9 in sections A, B, C, and D is also equal, so no abnormality is detected.

[0036] On the other hand, image 17d in Figure 12 shows a case where the thickness of workpiece 2 in sections A, B, and D is H1, while the thickness of workpiece 2 in section C is H3, which is thicker than H1 (H3 = H1 + H2). In this case, the measured amount of deflection of the suspension 9 in section C is smaller than the measured amount of deflection of the suspension 9 in sections A, B, and D (difference in deflection H4). That is, the amount of deflection of the suspension 9 in section C is smaller than the amount of deflection of the suspension 9 in sections A, B, and D, so it is possible to detect an abnormality in the thickness of workpiece 2 at the position of section C. When an abnormality is detected, the alarm 18 shown in Figure 5 may be sounded to notify the operator.

[0037] Furthermore, as a means of measuring the displacement of the suspension 9, a digital gauge 11e, which is a contact-type sensor as shown in Figure 3, may be used, or any means that can be obtained as an electrical signal or the like may be used. Alternatively, a strain gauge 11g or the like as shown in Figure 4 may be used.

[0038] As described above, in the polishing apparatus 1 of this embodiment, by measuring and converting the amount of deflection of multiple suspensions 9, it is possible to know the corresponding load state of the part supported by the suspension 9, and this can be used as information for more precise load control on the workpiece 2. As a result, it becomes possible to finely control the processing load applied to the workpiece 2.

[0039] Furthermore, by arbitrarily changing the amount of deflection of each suspension 9, the shape of the upper platen 8 can be controlled, and the direction of the load on the workpiece 2 can be precisely controlled.

[0040] Furthermore, when polishing multiple workpieces 2 simultaneously, if foreign matter or other substances adhere to any of the workpieces 2, causing an abnormality in the thickness of the workpiece 2, this abnormality can be detected. This allows the abnormal workpiece 2 to be removed and replaced with another workpiece 2.

[0041] Furthermore, when a turnbuckle 12f is used as the rotating body, the distance L1 between the upper platen 8 and the suspension 9 can be easily adjusted.

[0042] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from its essence. For example, in the above embodiment, the adjustment of the distance L1 between the upper platen 8 and the suspension 9 by the adjustment member 12 was described in the case where it is performed by a turnbuckle 12f. However, as shown in the second modified example in Figure 13, the adjustment of the distance L1 between the upper platen 8 and the suspension 9 may also be performed using an adjustment member 19. The adjustment member 19 has a holder 19b on which a roller 19a is provided that is positioned on the upper surface of the tip portion 9b of the suspension 9, a screw member 19d that is screw-coupled to the holder 19b, and an adjustment nut (rotating body) 19f that is screw-coupled to the screw member 19d. The head of the screw member 19d is rotatably held by a platen-side fixing portion 19e provided on the upper platen 8. A fixing nut 19c is positioned on the holder 19b side of the adjustment nut 19f, and when adjusting the distance L1 between the suspension 9 and the upper platen 8 by rotating the adjustment nut 19f, the fixing nut 19c is loosened to make the adjustment. An upper platen 8 equipped with such an adjustment member 19 may be used. [Explanation of Symbols]

[0043] 1... Polishing device, 2... Workpiece (workpiece), 3... Column section, 3a... Control section, 4... Operation panel, 5... Head section, 5a... Upper platen spindle, 6... Motor, 7... Air cylinder, 8... Upper platen, 8a... Polishing pad, 9... Suspension (suspension beam member), 9a... Base end, 9b... Tip, 10... Suspension base (drive unit), 11... Sensor, 11a... Optical displacement meter (non-contact sensor), 11b... Bracket, 11c... Light, 11d... Mirror, 11e... Digital gauge (contact sensor), 11f... Bracket, 11g... Strain gauge (sensor), 12... Adjustment member, 12a... Roller, 12b... Holder, 12c... Fixing nut, 12d...Beam-side threaded member, 12e...Surface plate-side threaded member, 12f...Turnbuckle (rotating body), 13...Lower surface plate, 13a...Polishing pad, 14...Carrier, 14a...Holding hole, 15...Sun gear, 16...Internal gear, 17...Display unit, 17a,17b,17c,17d...Image, 18...Alarm, 19...Adjustment member, 19a...Roller, 19b...Holder, 19c...Fixing nut, 19d...Threaded member, 19e...Surface plate-side fixing part, 19f...Adjustment nut (rotating body), D1,D2...Radial direction, F1,F2...Processing load, H1,H2,H3,H4...Height, L1,L2...Distance, R...Circumferential direction, Z...Vertical direction

Claims

1. A polishing device for polishing a workpiece, An upper platen spindle is incorporated, and a head unit is positioned above the workpiece so as to be able to move up and down, A top platen for polishing the upper surface of the workpiece, A drive unit provided at the lower end of the upper platen main shaft, Multiple suspension beam members, the base end of which is fixed to the drive body and the tip end of which is connected to the upper platen, to transmit the rotation of the upper platen's main shaft to the upper platen, A sensor for detecting the vertical displacement of each of the aforementioned suspension beam members, An adjustment member connects the suspension beam member and the upper platen, and adjusts the distance between the tip of the suspension beam member and the upper platen. A display unit that displays the vertical displacement of each of the suspension beam members based on the detection signals from the sensors, A polishing device having the following features.

2. The polishing apparatus according to claim 1, wherein the sensor is a contact-type or non-contact-type sensor that detects the amount of displacement of the tip of the suspension beam member.

3. The polishing apparatus according to claim 1, wherein the sensor is a strain gauge for detecting the amount of strain of the suspension beam member, and the polishing apparatus detects the amount of displacement of the suspension beam member based on the amount of strain.

4. In the polishing apparatus according to any one of claims 1 to 3, The aforementioned adjustment member is A polishing apparatus comprising: a holder provided with a roller positioned on the upper surface of the tip of the suspension beam member; a beam-side screw member screw-connected to the holder; a platen-side screw member facing the opposite direction from the beam-side screw member and screw-connected to the upper platen; and a rotating body screw-connected to the beam-side screw member and the platen-side screw member.

5. In the polishing apparatus according to claim 1, The aforementioned upper platen is disc-shaped, A polishing device in which each of the aforementioned suspension beam members extends radially to the upper platen and is arranged at regular intervals in the outer peripheral direction of the upper platen.

6. In the polishing apparatus according to claim 1, A lower platen for polishing the lower surface of the workpiece, Multiple carriers are provided, each having a holding hole for holding multiple workpieces, and are positioned on the lower base plate. Each of the aforementioned carriers has a sun gear that meshes with it, An internal gear is positioned radially outward from the sun gear and meshes with the carrier, A polishing device having a function for polishing both the upper and lower surfaces of the workpiece.

Images